By way of background, geometry involved does not permit the joints between a cylinder and a plate that is both strong, detachable and free of multiplicity of brackets, bracing and other reinforcement devices in building furniture such as tables, chairs, shelves, etc. and support stands for machinery and the like. Bending moments associated with such joints (table, chairs and the like) are high. Further, such brackets and braces and their associated bolts and screws lack aesthetic appearance and can be cumbersome to use. While metal joints can be welded together, this obviates simple onsite setting-up and breaking down. Non-metal joints can be glued but such glued joints are a weak link in the table. Neither of the above joints is reversibly detachable.
Brackets with an integral central threaded connection for the leg and an exterior plate which screws to the table top (plate) are disclosed in several U.S. and foreign patent documents. See for example U.S. Pat. No. 1,342,951 to Gagne, U.S. Pat. No. 1,762,776 to Gardner, U.S. Pat. No. 1,764,226 to Rennick, U.S. Pat. No. 4,199,124 to Tachida and U.S. Pat. No. 4,662,591 to Encontre; and Swedish Patent 128,750.
U.S. Pat. No. 2,607,648 to Metcalf and U.S. Pat. No. 4,735,390 to Richards disclose joints utilizing a welded bracket to which the leg is attached typically as a threaded connection.
Often the leg has been screwed directly to the table (see U.S. Pat. No. 1,877,098) and stretchers or the like braces have been employed to improve strength where necessary as in U.S. Pat. No. 2,099,450 to Meyer. Alternatively, the bracket is formed as an integral feature of the joint in question and the connector is a threaded peg or dual threaded screw. See U.S. Pat. No. 2,827,318 to White; French Patents 1,345,105; 494,930; 802,739; Swiss Patent 270,914; Danish Patent 50,055; and Austrian Patent 34,036.
U.S. Pat. No. 2,312,185 to Neuherz discloses a ferrule connector. Other patents of interest include U.S. Pat. No. 252,378 to Hoover and U.S. Pat. No. 5,588,624 to Woodham.
Heretofore, the bending moment at the end of a long lever arm has not been supported by enhancing the diameter of the threaded connection of the joint in a fashion suitable to produce a strong detachable joint that is also simple and aesthetic in appeal.